xref: /netbsd/sys/arch/arc/arc/timer.c (revision bf9ec67e)
1 /* $NetBSD: timer.c,v 1.1 2001/06/13 15:00:26 soda Exp $ */
2 /* NetBSD: clock.c,v 1.31 2001/05/27 13:53:24 sommerfeld Exp  */
3 
4 /*
5  * Copyright (c) 1988 University of Utah.
6  * Copyright (c) 1992, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * the Systems Programming Group of the University of Utah Computer
11  * Science Department and Ralph Campbell.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  * from: Utah Hdr: clock.c 1.18 91/01/21
42  *
43  *	@(#)clock.c	8.1 (Berkeley) 6/10/93
44  */
45 
46 #include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
47 
48 __KERNEL_RCSID(0, "$NetBSD: timer.c,v 1.1 2001/06/13 15:00:26 soda Exp $");
49 
50 #include <sys/param.h>
51 #include <sys/kernel.h>
52 #include <sys/systm.h>
53 
54 #include <arc/arc/timervar.h>
55 
56 struct device *timerdev;
57 const struct timerfns *timerfns;
58 int timerinitted;
59 
60 void
61 timerattach(dev, fns)
62 	struct device *dev;
63 	const struct timerfns *fns;
64 {
65 
66 	/*
67 	 * Just bookkeeping.
68 	 */
69 
70 	if (timerfns != NULL)
71 		panic("timerattach: multiple timers");
72 	timerdev = dev;
73 	timerfns = fns;
74 }
75 
76 /*
77  * Machine-dependent clock routines.
78  */
79 
80 /*
81  * Start the real-time and statistics clocks. Leave stathz 0 since there
82  * are no other timers available.
83  */
84 void
85 cpu_initclocks()
86 {
87 	if (timerfns == NULL)
88 		panic("cpu_initclocks: no timer attached");
89 
90 	tick = 1000000 / hz;	/* number of microseconds between interrupts */
91 	tickfix = 1000000 - (hz * tick);
92 	if (tickfix) {
93 		int ftp;
94 
95 		ftp = min(ffs(tickfix), ffs(hz));
96 		tickfix >>= (ftp - 1);
97 		tickfixinterval = hz >> (ftp - 1);
98         }
99 
100 	/*
101 	 * Get the clock started.
102 	 */
103 	(*timerfns->tf_init)(timerdev);
104 }
105 
106 /*
107  * We assume newhz is either stathz or profhz, and that neither will
108  * change after being set up above.  Could recalculate intervals here
109  * but that would be a drag.
110  */
111 void
112 setstatclockrate(newhz)
113 	int newhz;
114 {
115 
116 	/* nothing we can do */
117 }
118 
119 /*
120  * Wait "n" microseconds.
121  * XXX Should be calibrated with the cycle counter.
122  */
123 void
124 delay(n)
125 	int n;
126 {
127 
128 	DELAY(n);
129 }
130